[root@jw01 .ssh]# ssh-keygen -t rsa
[root@jw02 .ssh]# ssh-keygen -r rsa
[root@kt01  .ssh]# ssh-keygen -t rsa
[root@kt02  .ssh]# ssh-keygen -t rsa

Generating public/private rsa key pair.
Enter file in which to save the key (/root/.ssh/id_rsa): #回车代表无需密码登陆
Enter passphrase (empty for no passphrase): #回车
Enter same passphrase again: #回车
Your identification has been saved in /root/.ssh/id_rsa. #代表私钥
Your public key has been saved in /root/.ssh/id_rsa.pub. #代表公钥
The key fingerprint is:
04:45:0b:47:10:92:0c:b2:b9:d7:11:5b:49:05:e4:d9 root@jw01

例：192.168.4.200
[root@jw01 ~]# cd ~/.ssh
[root@jw01 .ssh]# ssh-copy-id -i  id_rsa.pub "-p 22 root@192.168.4.244"
[root@jw01 .ssh]# ssh-copy-id -i  id_rsa.pub "-p 22 root@192.168.4.232"
[root@jw01 .ssh]# ssh-copy-id -i  id_rsa.pub "-p 22 root@192.168.4.201"

root@192.168.4.244's password:              #输入密码
Now try logging into the machine, with "ssh '-p 22 root@192.168.4.244'", and check in:
 .ssh/authorized_keys
to make sure we haven't added extra keys that you weren't expecting.
以上信息出现就代表复制成功！